1. Field of the Invention
The present invention relates generally to a tube container, and more particularly relates to a tube container having an inner sleeve for containing a substance therein, an outer sleeve enclosing the inner sleeve, and a dispenser for discharging the substance from the inner sleeve.
2. Description of the Related Art
One example of a tube container of this kind, which has a dispenser attached to a tube body thereof, has been disclosed in Japanese Unexamined Utility Model Publication (Kokai) No. 3-17059. The disclosed tube container includes a tube body made of elastic material, which is gradually flattened along with the dispensing of the substance, and a dispenser coupled with a mouth portion of the tube body. The substance in the inner sleeve can be discharged by pushing and releasing a spout of the dispenser. The tube body tends to become flattened gradually as the contents is being discharged.
The tube container with a dispenser of this type has eliminated awkward operation by users, i.e., adjustment of a pressing force to be applied to the spout manually, because a certain amount of the contained substance can be discharged by simply pushing down the spout. Also, no substance is left remaining at the mouth portion and shoulder portion in the tube body after the contents is used up, because the contents can be almost completely discharged by a pump of the dispenser. Thus, the tube container so constructed is economical. Furthermore, since air does not come into the tube body during use, no oxidization of the contents or entry of undesirable microorganisms in the air will occur until the end of the usage of the tube container. Therefore, the users can use the container comfortably until emptied.
The tube container disclosed in the above publication, however, may have the following shortcomings. Firstly, the appearance may deteriorate during use because the tube body becomes flattened during discharge of the contents. Secondly, the commercial value of the tube body may be lessened since decorations applied onto the outer periphery of the tube body by printing, hot stamping and so forth become deformed by the aforementioned flattening of the tube body. Thirdly, it may become inconvenient for users to hold in hand, to place somewhere, or to operate the dispenser due to the flattening of the tube body.
In order to overcome the above-mentioned possible deficiencies and to maintain the initial shape of the tube container, one solution may be to employ the constitutions disclosed in Japanese Unexamined Utility Model Publication (Kokai) No. 59-51746 or Japanese Unexamined Patent Publication (Kokai) No. 58-193261. The tube container disclosed in the former document has a tube body with a laminated structure in which an outer sleeve and a soft inner sleeve holding contents therein are coupled at the mouth portion of the tube body. The bottom portion of each sleeve is sealed separately. In the outer sleeve, an opening is formed so as to communicate the inside of the outer sleeve with the outer air.
On the other hand, the tube container disclosed in the latter document is so constructed to have a double structure in which an inner sleeve made of an unrecoverable elastic member and an outer sleeve made of a recoverable elastic member are coupled at the mouth portion of the container. The bottom portion of each sleeve is sealed separately. An opening is formed through the outer sleeve.
With these tube containers, because only the inner tube is deformed along with the discharge of the contents, whereas the outer sleeve can maintain its initial shape due to entry of the air from the outside through the openings in the outer sleeve, the tube container as a whole can maintain its initial appearance. Therefore, deformation of decorations which are applied on the outer periphery of the tube body by printing, hot stamping, and so forth will not occur. Also, inconvenience in holding or handling the tube body is avoided, and placement of the container is facilitated.
However, considering application of the structures of the aforementioned conventional tube containers to other tube containers with a dispenser, there might be a problem that the inner sleeve may not be held stably in the outer sleeve because the bottom portions of both the outer sleeve and the inner sleeve are sealed separately and the inner sleeve is simply supported at the mouth portion of the container. It has been believed to be difficult to solve this problem, considering that the inner sleeve becomes flattened and shortened during use and discharge of the contents.
Moreover, with regard to manufacturing the tube containers of above described structures, it may be another problem that the manufacturing process thereof would be complicated because the bottom portions of the outer and the inner sleeve should be sealed in separate manufacturing steps.